For security purposes, most banks limit the amount you can withdraw from an ATM on a daily basis. Most of the time this isn't a problem, but perhaps you need money when traveling and aren't near a local bank branch or you've switched to an online bank that simply doesn't provide them. You can make larger withdrawals with your debit card by going to pretty much any bank and asking for a cash advance.

I recently switched from Bank of America to online bank Simple. I've never needed to withdraw more than $500 from an ATM for any reason, but, of course, ran into such a situation days after the switch. Simple doesn't have any physical branches, so if I wanted to use more funds I needed to use my debit card or have Simple send a check in the mail. I'd planned to buy something off Craigslist later that day, so neither of these options would work. I contacted them, asking if a workaround was available and learned about cash advances:

It cost me $1, but I was able to just walk into a nearby Chase branch and walk out with the money I needed in a few minutes. When you're in a bind and need access to your money, getting a "cash advance" through your debit card (which is not technically an advance seeing as you already have the money) can get the job done. It's important to note, however, that fees vary from bank to bank. Your bank may offer the service at no charge or you may have to pay a fair amount extra. Make sure to check before you act, just in case.